Insertion tools and methods for an electrical stimulation implant

ABSTRACT

In some embodiments, a method includes inserting at least a distal end portion of an insertion tool within a body. The distal end portion of the insertion tool is coupled to an electronic implant having a stimulation portion, a terminal portion and a substantially flexible conductor disposed between the stimulation portion and the terminal portion. The distal end portion of the insertion tool is moved within the body such that the stimulation portion of the electronic implant is disposed adjacent a target location and the terminal portion of the electronic implant is disposed beneath a skin of the body.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/187,662, filed on Aug. 7, 2008, entitled “Insertion Tools and Methodsfor an Electrical Stimulation Implant,” the disclosure of which isincorporated herein by reference in its entirety.

BACKGROUND

The invention relates generally to medical devices and procedures, andmore particularly to insertion tools and methods for implantingelectrical stimulation implants within the body.

Known electrical stimulation implants are used in various medicalprocedures. For example, some known electrical stimulation implants canbe implanted within a patient's body to stimulate a response from abodily organ or tissue, such as, for example, the heart, a muscle groupor the like. Some known electrical stimulation implants can include astimulation end, such as a cuff electrode, a pick-up end and aconductive portion therebetween. Such known electrical stimulationimplants can be inserted into the patient's body in a predeterminedlocation and/or orientation (e.g., such that the stimulation end islocated adjacent a target location and the pick-up end is locatedbeneath the skin).

Known methods for implanting an electrical stimulation implant within apatient's body can include first inserting the stimulation end of theimplant adjacent the target tissue, and then separately inserting thepick-up end of the implant under the surface of the skin. Such knownmethods, however, often include using multiple tools, such as, forexample, a tool to insert the stimulation end of the implant and adifferent tool to insert the pick-up end of the implant. Moreover, suchknown methods also include inserting the pick-up end of the implant intothe body via a pathway different from the pathway through which thestimulation end of the implant is inserted into the body.

Known methods for stimulating a desired target tissue via an electricalstimulation implant within a patient's body can include first placing apair of surface electrodes on the patient's skin. A current can then beconveyed transcutaneously from the surface electrode to the targettissue via the implant. Such known methods, however, can often result inweak stimulation due to attenuation of the current as the currenttravels within the body.

Thus, a need exists for improved methods and apparatus for implanting anelectrical stimulation implant within a patient's body. Additionally, aneed exists for improved methods of delivering current to an electricalstimulation implant within a patient's body.

SUMMARY

Methods and apparatus for inserting an electrical stimulation implantare described herein. In some embodiments, a method includes insertingat least a distal end portion of an insertion tool into a body. Thedistal end portion of the insertion tool is coupled to an electronicimplant having a stimulation portion, a terminal portion and asubstantially flexible conductor disposed between the stimulationportion and the terminal portion. The distal end portion of theinsertion tool is moved within the body such that the stimulationportion of the electronic implant is disposed adjacent a target locationand the terminal portion of the electronic implant is disposed beneath askin of the body.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of an insertion tool including anelectronic implant according to an embodiment.

FIG. 2 is a flow chart of a method of inserting the electronic implantinto the body using the insertion tool in FIG. 1.

FIGS. 3-5 are schematic illustrations showing a method of inserting theelectronic implant into the body using the insertion tool in FIG. 1.

FIGS. 6 and 7 are schematic illustrations of an implant delivery toolaccording to an embodiment in a first configuration and a secondconfiguration, respectively.

FIG. 8 is a perspective view of an implant delivery tool according to anembodiment.

FIG. 9 is a flow chart of a method of stimulating a target locationwithin a body according to an embodiment.

FIG. 10 is a schematic illustration of an electrical stimulation systemaccording to an embodiment.

FIG. 11 is a schematic illustration of an electrical stimulation systemaccording to an embodiment.

FIG. 12 is a plot of the absolute value of a simulated currentdistribution in a body of a patient along a longitudinal axis, accordingto an embodiment.

FIG. 13 is a schematic illustration of a longitudinal and a lateral axisacross an electronic implant disposed within a body, according to anembodiment.

FIG. 14 is a plot of the absolute value of the simulated currentdistribution in a body of a patient along a lateral axis, according toan embodiment.

DETAILED DESCRIPTION

In some embodiments, a method includes inserting at least a distal endportion of an insertion tool into a body. The distal end portion of theinsertion tool is coupled to an electronic implant having a stimulationportion, a terminal portion and a substantially flexible conductordisposed between the stimulation portion and the terminal portion. Thedistal end portion of the insertion tool is moved within the body suchthat the stimulation portion of the electronic implant is disposedadjacent a target location and the terminal portion of the electronicimplant is disposed beneath a skin of the body.

In some embodiments, an apparatus includes an implant delivery toolconfigured to deliver at least a portion of an electronic implant withina body. The implant delivery tool includes a guide member and aninsertion member. The guide member has a distal end portion configuredto contact an outer surface of a skin of the body. Additionally, thedistal end portion of the guide member is configured to move relative tothe outer surface of the skin. The insertion member is configured todeliver the portion of the electronic implant into the body when thedistal end portion of the guide member is moved relative to the outersurface of the skin.

In some embodiments, a method includes operatively coupling anelectrical device disposed outside of a body to a first electrode and asecond electrode. The first electrode is coupled to a first portion of askin of the body and the second electrode is coupled to a second portionof the skin. An electrical signal from the electrical device is conveyedinto the body via the first electrode such that a first portion of theelectrical signal travels within the body along a first path and asecond portion of the electrical signal travels within the body along asecond path. The first path, which can be, for example, a firststimulation path, includes the first portion of the skin, the secondportion of the skin and a target location within the body. The targetlocation can be, for example, a median nerve, a peripheral nerve, asuperficially located nerve or the like. The second path, which can be,for example, a second stimulation path, includes the first portion ofthe skin, the second portion of the skin and an electronic implantdisposed within the body.

As used in this specification, the words “proximal” and “distal” referto the direction closer to and away from, respectively, an operator(e.g., surgeon, physician, nurse, technician, etc.) who would use amedical device during a procedure. For example, the end of a medicaldevice first to contact and/or be inserted into the patient's body wouldbe the distal end, while the opposite end of the medical device (e.g.,the end of the medical device being operated by the operator) would bethe proximal end of the medical device.

The term “electronic implant” as used herein can refer to either animplant including active electronic circuitry or an implant including apassive portion of an electronic circuit system, unless otherwisespecified. For example, as used herein, an electronic implant caninclude active devices, such as microstimulators, amplifiers, powersupplies, sensors or the like. An electronic implant can also includepassive devices, such as passive conductors, leads, wires, or the like.

FIG. 1 is a schematic illustration of an insertion tool 100 and anelectronic implant 110 according to an embodiment of the invention. Theinsertion tool 100 includes a distal end portion 102 and a proximal endportion (not shown). The electronic implant 110 is coupled to the distalend portion 102 of the insertion tool 100 and includes a stimulationportion 113, a terminal portion 115 and a conductor 118. The conductor118, which is constructed of a substantially flexible material, isdisposed between the stimulation portion 113 and the terminal portion115 of the electronic implant 110. The insertion tool 100 is configuredto insert an electronic implant 110 within a body of a patient. In someembodiments, the stimulation portion 113 of the electronic implant 110stimulates a target location within the body. In some embodiments, thetarget location can be a median nerve, a peripheral nerve, asuperficially located nerve or the like.

In some embodiments, the insertion tool 100 defines a lumen (not shown)within which the electronic implant 110 can be disposed. In otherembodiments, the electronic implant 110 can be coupled to an outersurface of the distal end portion 102 of the insertion tool 100.Although FIG. 1 shows the electronic implant 110 being coupled to thedistal end portion 102 of the insertion tool 100 such that thestimulation portion 113 of the electronic implant 110 extends beyond thedistal end portion 102 of the insertion tool 100, in some embodiments,the electronic implant 110 can be coupled to the insertion tool 100 suchthat the stimulation portion 113 is flush with or recessed from thedistal end portion 102 of the insertion tool 100.

The distal end portion 102 of the insertion tool 100 and the electronicimplant 110 can be coupled together by any suitable means. For example,the distal end portion 102 of the insertion tool 100 and the electronicimplant 110 can be coupled together by a mechanical coupling (e.g., aninterference fit, detents, a threaded coupling, or the like), anelectronic coupling (e.g., a magnetic coupling), a chemical bond, ahydraulic coupling and/or a pneumatic coupling (e.g., a vacuumcoupling). Although the electronic implant 110 is shown as being coupledto the distal-most portion of the insertion tool 100, in otherembodiments, the electronic implant 110 can be coupled in any suitablelocation along the distal end portion 102 of the insertion tool 100.

The insertion tool 100 can be any suitable shape and/or size tofacilitate percutaneous insertion of the insertion tool 100 within thebody. For example, the insertion tool 100 can have a cylindrical shapeand a diameter of approximately 1 millimeter. In some embodiments, thedistal end portion 102 of the insertion tool 100 can have a taperedportion. In some embodiments, however, the insertion tool 100 can beused during an open surgery and can be any suitable size and/or shape tofacilitate such insertion.

FIG. 2 is a flow chart of a method 220 of disposing the electronicimplant 110 within the body B according to an embodiment of theinvention. The method illustrated in FIG. 2 is discussed with referenceto FIGS. 3-5, which are schematic illustrations of the electronicimplant 110 disposed within a body B in a first configuration, a secondconfiguration and a third configuration, respectively. The methodincludes inserting at least a distal end portion of an insertion toolhaving an electronic implant coupled thereto into a body, 221. Referringto FIG. 3, at least the distal end portion 102 of the insertion tool 100is inserted into a body B of a patient through skin incision I. In someembodiments, the electronic implant 110 is coupled to the distal endportion 102 of the insertion tool 100 such that the stimulation portion113 of the electronic implant 110 is inserted into the body B along withthe distal end portion 102 of the insertion tool 100.

As shown in FIG. 3, the insertion tool 100 is inserted within the body Balong the longitudinal axis L_(A) of the insertion tool 100 at an anglex such that the insertion tool 100 is directed toward a target locationT within the body B. In some embodiments, for example, the targetlocation T can be a median nerve, a peripheral nerve, a superficiallylocated nerve or the like. In some embodiments, the method can includeinserting the insertion tool 100 such that the angle x of insertion isless than 30 degrees. Said another way, in some embodiments, thelongitudinal axis L_(A) of the insertion tool 100 can be offset from theskin S of the body B at an angle less than 30 degrees. In this manner,the insertion tool 100 can deliver the electronic implant 110 to ashallow target location within the body B.

Returning to the flow chart shown in FIG. 2, the distal end portion ofthe insertion tool is moved within the body such that the stimulationportion of the electronic implant is disposed adjacent the targetlocation and a terminal portion of the electronic implant is disposedbeneath the skin, 222. As shown in FIG. 4, the insertion tool 100 ismoved within the body B along the longitudinal axis L_(A) of theinsertion tool 100 in a direction AA, toward the target location T. Thedistal end portion 102 of the insertion tool 100 is moved along aninsertion path P within the body B such that the stimulation portion 113of the electronic implant 110 is adjacent the target location T. Saidanother way, the distal end portion 102 of the insertion tool 100 ismoved such that the stimulation portion 113 of the electronic implant110 is spaced apart from the target location T within the patient's bodyB by a predetermined distance. Similarly stated, the stimulation portion113 of the electronic implant 110 is positioned proximate a particularanatomical structure (e.g., a nerve, muscle, or the like), at a desireddepth or the like. Although the stimulation portion 113 is shown asbeing adjacent the target location T, in other embodiments, theinsertion tool 100 can be moved along the insertion path P such that thestimulation portion 113 of the electronic implant 110 is in contact withthe target location T.

As shown in FIG. 4, the distal end portion 102 of the insertion tool 100is moved along the insertion path P within the body B such that theterminal portion 115 of the electronic implant 110 is disposed beneaththe skin S of the body B. In this manner, the stimulation portion 113and the terminal portion 115 are implanted within the body B using theinsertion tool 100, in a single motion. In some embodiments, thestimulation portion 113 and the terminal portion 115 of the electronicimplant 110 are each disposed within the insertion path P. In someembodiments, the insertion tool 100 is moved within the body B such thatthe distal end portion 102 of the insertion tool 100 and/or thestimulation portion 113 of the insertion tool 100 defines the insertionpath P. In some embodiments, for example, the distal end portion 102 ofthe insertion tool 100 can be configured to pierce, dilate and/ordisplace bodily tissue to define the insertion path P. In otherembodiments, the insertion path P can be formed by a separate tool, suchas, for example, an insertion probe, a trocar or the like.

Returning to the flow chart shown in FIG. 2, in some embodiments, theinsertion tool can be removed from the body, 223. As shown in FIG. 5,the insertion tool 100 is removed from the body B such that theelectronic implant 110 remains in the body B at a predeterminedlocation. Said another way, the electronic implant 110 substantiallymaintains a position within the body B after the insertion tool 100 isremoved. In this manner, the stimulation portion 113 of the electronicimplant 110 is adjacent the target location T at a predetermined depth,d₂, beneath the skin S of the body B. Similarly, the terminal portion115 of the electronic implant 110 is beneath the skin S of the body B ata predetermined depth, d₁.

FIGS. 6 and 7 are schematic illustrations of an implant delivery tool500 in a first configuration and a second configuration, respectively.The implant delivery tool 500 includes a guide member 530 and aninsertion member 540. The guide member 530 of the implant delivery tool500 includes a distal end portion 532 configured to contact an outersurface of a skin S of a body B and to move relative to the outersurface of the skin S.

The distal end portion 532 of the guide member 530 can have any sizeand/or shape to facilitate movement of the guide member 530 along theouter surface of the skin S. Said another way, the guide member 530 canhave any size and/or shape that prevents the distal end portion 532 ofthe guide member 530 from catching and/or engaging the skin S such thatthe movement of the distal end portion 532 relative to the skin S isdisrupted. In some embodiments, the distal end portion 532 of the guidemember 530 can have a spherical shape to facilitate the movement of theguide member 530 along the outer surface of the skin S. In someembodiments, the distal end portion 532 of the guide member 530 canslide along the outer surface of the skin S Similarly stated, the distalend portion 532 of the guide member 530 can translate along the outersurface of the skin S. In other embodiments, the distal end portion 532of the guide member 530 can roll along the outer surface of the skin SSimilarly stated, the distal end portion 532 of the guide member 530 canrotate along the outer surface of the skin S.

The insertion member 540 of the implant delivery tool 500 includes adistal end portion 542 configured to be disposed within the body B. Theinsertion member 540 is configured to be coupled to an electronicimplant 510. The electronic implant 510 can be, for example, amicrostimulator, an elongate implant, an electronic lead, an electrode,a sensor and/or the like. In some embodiments, the insertion member 540defines a lumen (not shown) within which at least a portion of theelectronic implant 510 can be disposed. In some embodiments, at least aportion of the insertion member 540 can have an arcuate shape tofacilitate the insertion of the electronic implant 510. In someembodiments, however, the insertion member 540 can be any size and/orshape to facilitate the delivery of the electronic implant 510 into thebody B.

As shown in FIGS. 6 and 7, the guide member 530 is coupled to theinsertion member 540 such that the movement of the guide member 530results in the movement of the insertion member 540. In this manner, theguide member 530 is configured to guide the insertion member 540 withinthe body B during insertion of the insertion member 540. Similarlystated, the guide member 530 is configured to maintain the insertionmember 540 at a predetermined depth within the body B when the insertionmember 540 is inserted into the body B. Thus, a portion of an electronicimplant 510 can be delivered into the body B via the insertion member540 when the distal end portion 532 of the guide member 530 is movedrelative to the outer surface of the skin S.

In the first configuration, as shown in FIG. 6, the implant deliverytool 500 is moved in direction CC such that the guide member 530 movesalong the outer surface of the skin S and guides distal end portion 542of the insertion member 540 as it is inserted into the body B via skinincision I. The shape of the insertion member 540 can define the pathalong which the insertion member 540 moves within the body B. In someembodiments, the insertion member 540 moves within the body B along apath formed by a separate tool, such as, for example, an insertionprobe, a trocar or the like. As more of the insertion member 540 isinserted into the body, the implant delivery tool moves from the firstconfiguration to the second configuration, as shown in FIG. 7. Similarlystated, when moved from the first configuration to the secondconfiguration, the insertion tool 500 is moved in direction DDsubstantially parallel to the outer surface of the skin S The insertiontool 500 is moved in direction DD until the electronic implant 510 is atits predetermined target location.

FIG. 8 is a schematic illustration of an implant delivery tool 600according to an embodiment of the invention. The implant delivery tool600 includes a guide member 630, an insertion member 640 and a handle650. The insertion member 640 and the guide member 630 are coupledtogether via the handle 650. The handle 650 is shaped such that a usercan grasp the handle 650 to maneuver the implant delivery tool 600. Thehandle 650 can be any shape and/or size to facilitate the maneuvering ofthe implant delivery tool 600, such as, for example, a bulb shape.

The guide member 630 of the implant delivery tool 600 includes a distalend portion 632 configured to contact an outer surface of a skin S of abody B and to move relative to the outer surface of the skin S along alongitudinal axis L_(A). The distal end portion 632 of the guide member630 includes a spherical portion 633 to facilitate a movement of theguide member 630 along the outer surface of the skin S along thelongitudinal axis L_(A). Specifically, the distal end portion 632 of theguide member 630 slides along the outer surface of the skin S along thelongitudinal axis L_(A). Similarly stated, the distal end portion 632 ofthe guide member 630 translates along the longitudinal axis L_(A). Inthis manner, the spherical portion 633 of the guide member 630 preventsthe distal end portion 632 from catching and/or engaging the skin S suchthat the movement of the distal end portion 632 relative to the skin Sis disrupted. In some embodiments, the spherical portion 633 of theguide member 630 can roll along the outer surface of the skin SSimilarly stated, the spherical portion 633 of the guide member 630 canrotate along the outer surface of the skin S

The insertion member 640 includes a distal end portion 642 configured tobe disposed within the body B, as shown in FIG. 8. The insertion member640 is configured to be coupled to an electronic implant (not shown).The electronic implant can be, for example, a microstimulator, anelongate implant, an electronic lead, an electrode, a sensors and/or thelike. The insertion member 640 has an arcuate shape to facilitate theinsertion of the electronic implant (not shown). In some embodiments,however, the insertion member 640 can be any size or shape to facilitatethe delivery of the electronic implant into the body B. In someembodiments, the insertion member 640 is configured to be coupled to theelectronic implant such that a portion of the electronic implant can bedelivered into the body B via skin incision I when the distal endportion 632 of the guide member 630 is moved relative to the outersurface of the skin S.

The guide member 630 and the insertion member 640 are positionedrelative to each other at an angle α. Said another way, the insertionmember 640 is oriented at angle α relative to the longitudinal axisL_(A) of the guide member 630. In this manner, the distal end portion632 of the guide member 630 is separated from the distal end portion 642of the insertion member 640 by a distance d₄. In some embodiments, auser, such as, for example, a surgeon, can determine the angle α oforientation of the guide member 630 relative to the insertion member 640and/or the distance d₄ between the guide member 630 and the insertionmember 640.

As shown in FIG. 8, the distal end portion 642 of the insertion member640 is displaced from the end of the spherical portion 633 of the guidemember 630 along the longitudinal axis L_(A) of the guide member 630 bya distance d₅. In other embodiments, however, the distal end portion 642of the insertion member 640 can be flush with the spherical portion 633of the guide member 630. In yet other embodiments, the distal endportion 642 of the insertion member 640 can extend beyond the sphericalportion 633 of the guide member 630.

In some embodiments, the spherical portion 633 can include an electronicdevice configured to convey information back to a user. Such informationcan be, for example, information relating to the location of theinsertion member 640 within the body B. In other embodiments, thespherical portion 633 of the guide member 630 can be configured toelectrically stimulate a target location within the body B.

In some embodiments, the distal end portion 642 of the insertion member640 is configured to locate a target location within the body B. Forexample, in some embodiments, the distal end portion 642 of theinsertion member 640 can include a target probe having an exposedelectrode configured to stimulate a muscle, a nerve or the like and/orreceive an electronic signal from a muscle, nerve or the like to locatethe target location.

In some embodiments, the handle 650 can be configured to adjust theangle α of orientation between the guide member 630 and the insertionmember 640. Similarly, the handle 650 can be configured to adjust thedistance d₄ between the distal end portion 632 of the guide member 630and the distal end portion 642 of the insertion member 640.

In some embodiments, the insertion member 640 can include a plurality ofgraduated markings configured to indicate a position of the distal endportion 642 of the insertion member 640 within the body B. In someembodiments, the insertion member 640 can be configured to have anadjustable length.

In some embodiments, the insertion member 640 and/or the guide member630 of the implant delivery tool 600 can be similar to portions of theinsertion tool shown in U.S. patent application Ser. Nos. 11/972,393,11/972,396, and 11/972,402 to Glukhovsky, which are incorporated byreference for all purposes as if fully set forth herein.

FIG. 9 is a flow chart of a method 760 of stimulating a target locationT within a body B according to an embodiment of the invention. Themethod illustrated in FIG. 9 is discussed with reference to FIG. 10,which is a schematic illustration of an electrical stimulation system870 for stimulating a target location T within a body B. The methodincludes operatively coupling an electrical device disposed outside of abody to a first electrode and a second electrode, 761. Referring to FIG.10, the electrical stimulation system 870 includes an electrical device872, a first electrode 875 and a second electrode 876. The electricaldevice 872 is operatively coupled to the first electrode 875 via a firstconnection 873. Similarly, the electrical device 872 is operativelycoupled to the second electrode 876 via a second connection 874. Theelectrical device 872 is configured to generate and send an electricalsignal to the first electrode 875 and/or the second electrode 876 viaconnections 873 and 874, respectively. In some embodiments, for example,the electrical device 872 can produce an electrical current havingcharacteristics suitable for therapeutic stimulation. In someembodiments, the connections 873 and 874 are wires. In some embodiments,the connections 873 and 874 are direct electrical contacts between theelectrical device 872 and the electrodes 875 and 876.

The first electrode 875 and the second electrode 876 are surfaceelectrodes disposed on an outer surface of a skin S of the body B. Morespecifically, the first electrode 875 is coupled to a first portion S₁of the skin S and the second electrode 876 is coupled to a secondportion S₂ of the skin S. In some embodiments, the first electrode 875and the second electrode 876 are spaced apart from each other by apredetermined distance. Said another way, in some embodiments, the firstportion S₁ of the skin S is disposed apart from the second portion S₂ ofthe skin S The location of the electrodes 875 and 876 can be maintainedby any suitable means, such as, for example, a conductive gel, adhesive,a fitted garment or the like. The electrodes 875 and 876 can be anysuitable electrode for transmitting and/or receiving an electricalsignal to or from the body B. For example, in some embodiments, theelectrodes 875 and 876 can be gel electrodes. In other embodiments, theelectrodes 875 and 876 can be flexible disc-type electrodes havingelectrical leads. Similarly, the electrodes 875 and 876 can beconstructed from any suitable material, such as, for example, conductiveelectrolyte gel, conductive rubber, conductive plastic, metal mesh,metal plate, metallized rubber and/or plastic.

As shown in FIG. 10, an electronic implant 810 is disposed beneath theskin S of the body B. The electronic implant 810 includes a stimulationportion 813, a terminal portion 815 and a conductor 818. The conductor818 is disposed between the stimulation portion 813 and the terminalportion 815 of the electronic implant 810. The stimulation portion 813of the electronic implant 810 is disposed adjacent a target location Tand is configured to electrically stimulate the target location T. Asshown in FIG. 10, the second electrode 876 is coupled to the skin S in alocation above the stimulation portion 813 of the electronic implant810. In some embodiments, the second electrode 876 can be coupled to theskin at a location directly above the stimulation portion 813 of theelectronic implant 810 and/or the target location T. The first electrode875 is coupled to the skin S in a location adjacent the terminal portion815 of the electronic implant 810. In some embodiments, the firstelectrode 875 can be coupled to the skin S at a location directly abovethe terminal portion 815 of the electronic implant 810.

Returning to the flow chart shown in FIG. 9, an electrical signal isconveyed from the electrical device into the body via the firstelectrode such that a first portion of the electrical signal travelswithin the body along a first path and a second portion of theelectrical signal travels within the body along a second path, 762.Referring to FIG. 10, the electrical device 872 conveys an electricalsignal (e.g., current) transcutaneously into the body B via the firstelectrode 875. When the electrical signal is conveyed into the body B, afirst portion I₁ of the signal travels along a first path P₁ and asecond portion I₂ of the signal travels along a second path P₂. Thefirst path P₁, which can be, for example, a first stimulation path,includes the first electrode 875, the electronic implant 810 and thesecond electrode 876. In this manner, the first portion I₁ of theelectrical signal travels along the first path P₁ from the firstelectrode 875 to the terminal portion 815 of the electronic implant 810,through the first portion S₁ of the skin S of the body B. The firstportion I₁ of the electrical signal is received by the terminal portion815 of the electronic implant 810 and is conveyed to the stimulationportion 813 of the electronic implant 810 via the conductor 818. Thus,first portion I₁ of the electrical signal stimulates the target locationT via the stimulation portion 813 of the electronic implant 810. Thefirst portion I₁ of the electrical signal is transmitted back to thesecond electrode 876, through the second portion S₂ of the skin S of thebody B, to complete the electrical circuit.

As shown in FIG. 10, the second path P₂, which can be, for example, asecond stimulation path, includes the first electrode 875, the targetlocation T and the second electrode 876. In this manner, the secondportion I₂ of the electrical signal travels along the second path P₂from the first electrode 875 to the target location T, through the firstportion S₁ of the skin S of the body B, such that the target location Tis stimulated via the second portion I₂ of the electrical signal. Thesecond portion I₂ of the electrical signal is transmitted back to thesecond electrode 876, through the second portion S₂ of the skin S of thebody B, to complete the electrical circuit.

FIG. 11 is a schematic illustration of a electrical stimulation system970 for stimulation of a target location T within a body B. Theelectrical stimulation system 970 includes an electrical device 972, afirst electrode 975 and a second electrode 976. The electrical device972 is operatively coupled to the first electrode 975 via a firstconnection 973. Similarly, the electrical device 972 is operativelycoupled to the second electrode 976 via a second connection 974. Theelectrical device 972 is configured to generate and send an electricalsignal to the first electrode 975 and/or the second electrode 976 viaconnections 973 and 974, respectively. In some embodiments, for example,the electrical device 972 can produce an electrical current havingcharacteristics suitable for therapeutic stimulation. In someembodiments, the connections 973 and 974 are wires. In some embodiments,the connections 973 and 974 are direct electrical contacts between theelectrical device 972 and the electrodes 975 and 976.

The first electrode 975 and the second electrode 976 are surfaceelectrodes disposed on an outer surface of a skin S of the body B. Morespecifically, the first electrode 975 is coupled to a first portion S₃of the skin S and the second electrode 976 is coupled to a secondportion S₄ of the skin S, as described above with reference to FIG. 10.In some embodiments, the first electrode 975 and the second electrode976 are spaced apart from each other by a predetermined distance. Saidanother way, in some embodiments, the first portion of the skin S isdisposed apart from the second portion of the skin S. The location ofthe electrodes 975 and 976 can be maintained by any suitable means, asdescribed above. The electrodes 975 and 976 can be any suitableelectrode for transmitting and/or receiving an electrical signal to orfrom the body B, as described above.

As shown in FIG. 11, an electronic implant 910 is disposed beneath theskin S of the body B. The electronic implant 910 includes a stimulationportion 913, a terminal portion 915 and a conductor 918. The conductor918 is disposed between the stimulation portion 913 and the terminalportion 915 of the electronic implant 910. The stimulation portion 913of the electronic implant 910 is disposed adjacent a target location Tand is configured to electrically stimulate the target location T. Asshown in FIG. 15, the electronic implant 910 has length such that theterminal portion 915 of the electronic implant 910 is disposed below thefirst electrode 975 and the stimulation portion 913 of the electronicimplant 910 is disposed below the second electrode 976. Said anotherway, the second electrode 976 is coupled to the skin S in a locationabove the stimulation portion 913 of the electronic implant 910. In someembodiments, the second electrode 976 can be coupled to the skin at alocation directly above the stimulation portion 913 of the electronicimplant 910 and/or the target location T. Similarly, the first electrode975 is coupled to the skin S in a location above the terminal portion915 of the electronic implant 910. In some embodiments, the firstelectrode 975 can be coupled to the skin S at a location directly abovethe terminal portion 915 of the electronic implant 910.

As shown in FIG. 11, the electrical device 972 conveys an electricalsignal (e.g., current) transcutaneously into the body B via the firstelectrode 975. When the electrical signal is conveyed into the body B, afirst portion I₃ of the signal travels along a first path P₃ and asecond portion I₄ of the signal travels along a second path P₄. Thefirst path P₃, which can be, for example, a first stimulation path,includes the first electrode 975, the electronic implant 910 and thefirst electrode 976. In this manner, the first portion I₃ of the signaltravels along the first path P₃ from the first electrode 975 to theterminal portion 915 of the electronic implant 910, through the firstportion S₃ of the skin S of the body B. The first portion I₃ of thesignal is received by the terminal portion 915 of the electronic implant910 and is conveyed to the stimulation portion 913 of the electronicimplant 910 via the conductor 918. Thus, the first portion I₃ of thesignal stimulates the target location T via the stimulation portion 913of the electronic implant 910. The first portion I₃ of the signal istransmitted back to the second electrode 976, through the second portionS₄ of the skin S of the body B, to complete the electrical circuit.

The second path P₄, which can be, for example, a second stimulationpath, includes the first electrode 975, the target location T and thesecond electrode 976. In this manner, the second portion I₄ of thesignal travels along the second path P₄ from the first electrode 975 tothe target location T, through the first portion S₃ of the skin S of thebody B, such that the target location T is stimulated via the secondportion I₄ of the signal. The second portion I₄ of the signal istransmitted back to the second electrode 976, through the second portionS₄ of the skin S of the body B, to complete the electrical circuit.

As shown in FIGS. 10 and 11, the electrical stimulation system 870 and970 can be placed on the skin S, above the electronic implant 810 and910, in different configurations. The different configurations can beused to tailor stimulation to the target location T. Said another way,the configurations can be used to fine tune the stimulation such thatattenuation of the electrical signal is minimized as the electricalsignal is conveyed in the body B. Similarly stated, the configurationscan be used to maximize the amount of the electrical signal that reachesthe target location T. For example, in some embodiments, the electronicimplant can have a short lead length such that the first electrode ispositioned on the skin above the terminal portion of the electronicimplant and the second electrode is positioned on the skin above thestimulation portion of the electronic implant. In this manner, thedistance the first portion of the electrical signal has to travel to theterminal portion and the distance the second portion of the electricalsignal has to travel to the target location T is minimized. Thus, agreater amount of the electrical signal reaches the target location Tsuch that attenuation of the electrical signal is minimized. As aresult, the electrical stimulation systems 870 and 970 are well-suitedfor shallow depth stimulation.

FIG. 12 is a plot 1080 of a simulated current distribution within thebody B along a longitudinal axis L_(LONG) of the stimulation portion 813and 913 of the electronic implant 810 and 910. Specifically, the plot1080 illustrates the simulated current distribution within the body Balong an axis substantially parallel to the skin S of the body B, asshown in FIG. 13. Said another way, the plot 1080 illustrates thesimulated current distribution within the body B along an axissubstantially coaxial with the stimulation portion 813 and 913 of theelectronic implant 810 and 910.

Referring to FIG. 12, a longitudinal current distribution 1081 of theelectrical stimulation system 870 is represented by a dashed line and alongitudinal current distribution 1082 of the electrical stimulationsystem 970 is represented by a solid line. The current distributions1081 and 1082 are representative of the net current distribution in thebody B. More particularly, the current distribution 1081 is illustrativeof the current distributed via the first portion I₁ and the secondportion I₂ of the electrical signal. Similarly, the current distribution1082 is illustrative of the current distributed via the first portion I₃and the second portion I₄ of the electrical signal. Although the plot1080 is shown as having numerical values on the x-axis and y-axis, suchvalues are merely exemplary values. The x-axis of the plot 1080 is aspatial axis, which can be, for example, a distance from the targetlocation T. The y-axis of the plot 1080 can have any relative value,such as, for example, current in Amperes.

As shown in FIG. 12, the highest amounts of current distribution withinthe body B are the areas nearest to the target location T. Specifically,the highest amounts of current distribution within the body B is locatedat points A and A′ for electrical stimulation system 970 and at points Band B′ for electrical stimulation system 870. The peak areas A, A′, Band B′ facilitate or help facilitate the stimulation of the targetlocation T. More particularly, the higher current distributions withinthe body B nearest the target location T have a higher probability ofactivating the target location T. As described above, the amount ofcurrent distribution within the body B can be adjusted or tuned by thepositioning of the electrodes of the electrical stimulation system.

FIG. 14 is a plot 1090 of a simulated current distribution within thebody B along a lateral axis L_(LAT) of the stimulation portion 813 and913 of the electronic implant 810 and 910. Specifically, the plot 1090illustrates the simulated current distribution within the body B alongan axis substantially perpendicular to the skin S of the body B, asshown in FIG. 13. Referring to FIG. 14, a lateral current distribution1091 of the electrical stimulation system 870 is represented by a dashedline and a lateral current distribution 1092 of the electricalstimulation system 970 is represented by a solid line. The currentdistributions 1091 and 1092 are representative of the net currentdistribution in the body B, as described above with reference to plot1080. Although the plot 1090 is shown as having numerical values on thex-axis and y-axis, such values are merely exemplary values. The x-axisof the plot 1090 is a spatial axis, which can be, for example, adistance beneath the skin S. The y-axis of the plot 1090 can have anyrelative value, such as, for example, current in Amperes.

As shown in FIG. 14, the highest amounts of current distribution withinthe body B is the area between the skin S (axis=0) and the targetlocation T. Thus, the amount of current distribution within the body Bcan be adjusted or tuned by the positioning of the electrodes of anelectrical stimulation system and/or the depth of a stimulation portionof an electronic implant.

FIGS. 12 and 14, combined, provide a 3D illustration of the net currentdistribution in the body B. As described above, the positioning of theelectrodes 875, 876, 975 and 976 of the electrical stimulation systems870 and 970 on the skin S and/or the positioning of the electronicimplants 810 and 910 within the body can facilitate the adjustment ofthe magnitude of current reaching the target location T such that adesired stimulation at the target location T can be attained. Forexample, in some embodiments, the length of the electronic implant canbe shortened such that the first electrode is positioned on the skinabove the terminal portion of the electronic implant and the secondelectrode is positioned on the skin above the stimulation portion of theelectronic implant. In this manner, the distance the first portion andthe second portion of the electrical signal has to travel to the targetlocation T is minimized such that attenuation of the electrical signalis minimized. As a result, a greater magnitude of current reaches thetarget location T.

While various embodiments of the invention have been described above, itshould be understood that they have been presented by way of exampleonly, and not limitation. Where methods described above indicate certainevents occurring in certain order, the ordering of certain events may bemodified. Additionally, certain of the events may be performedconcurrently in a parallel process when possible, as well as performedsequentially as described above.

For example, although the electrical signal is shown and described aboveas being an electrical current, in some embodiments, the electricalsignal can be any stimulation signal to facilitate the stimulation ofthe target location T. For example, in some embodiments, the electricalsignal can be an ultrasonic stimulation wave. In other embodiments, theelectrical signal can be a radio frequency signal, an optical signal, asonic signal or the like.

Although the electrodes 875, 876, 975 and 976 are shown and describedabove as being coupled to the skin S to provide transcutaneouselectrical stimulation to a target location T within the body B, in someembodiments, at least an electrode 875, 876, 975 and 976 can be disposedwithin the body B to provide subcutaneous electrical stimulation to atarget location T within the body B.

In some embodiments, the electrical stimulation system 870 and 970 canbe configured to tune the timing of the stimulation to the targetlocation T. For example, in some embodiments, the electrodes 875, 876,975 and 976 can be positioned on the skin S relative to the electronicimplant 810 and 910 and/or target location T such that the first portionI₁ and I₃ of the electrical signal and the second portion I₂ and I₄ ofthe electrical signal stimulates the target location T at the same time.In other embodiments, the electrodes 875, 876, 975 and 976 can bepositioned to produce a phase difference between the first portion I₁and I₃ of the electrical signal and the second portion I₂ and I₄ of theelectrical signal such that the first portion I₁ and I₃ of theelectrical signal and the second portion I₂ and I₄ of the electricalsignal stimulate the target location T at different times. In some suchembodiments, the timing of the stimulation can be adjusted based on theposition of the electrodes 875, 876, 975 and 976 on the skin relative tothe electronic implant 810 and 910 and/or target location T.

In some embodiments, the proximal end portion 102 of the insertion tool100 can include an electronic device configured to convey informationback to a user. Such information can be, for example, informationrelating to the location of the insertion tool 100 within the body B. Inother embodiments, the proximal end portion 102 of the insertion tool100 can be configured to electrically stimulate a target location withinthe body B.

In some embodiments, the proximal end portion 102 of the insertion tool100 is configured to locate a target location within the body B. Forexample, in some embodiments, the proximal end portion 102 of theinsertion tool 100 can include a target probe having an exposedelectrode configured to stimulate a muscle, a nerve or the like and/orreceive an electronic signal from a muscle, nerve or the like to locatethe target location.

In some embodiments, the insertion tool 100 can include a plurality ofgraduated markings configured to indicate a position of the proximal endportion 102 of the insertion tool 100 within the body B. In someembodiments, the insertion tool 100 can be configured to have anadjustable length.

Although various embodiments have been described as having particularfeatures and/or combinations of components, other embodiments arepossible having a combination of any features and/or components from anyof embodiments where appropriate. For example, in some embodiments, theinsertion tool 100 can include a handle coupled to a distal end portion(not shown in FIG. 1) of the insertion tool 100 to facilitate themaneuvering of the insertion tool 100 within the body B. The handlecould be, for example, the handle 650 of the implant delivery tool 600illustrated in FIG. 8.

What is claimed is:
 1. A method, comprising: inserting at least a distalend portion of an insertion tool within a body, the distal end portionof the insertion tool coupled to an electronic implant, the electronicimplant having a stimulation portion, a terminal portion, and asubstantially flexible conductor disposed between the stimulationportion and the terminal portion; and moving the distal end portion ofthe insertion tool within the body such that the stimulation portion ofthe electronic implant is disposed adjacent a target location and theterminal portion of the electronic implant is disposed beneath a skin ofthe body.
 2. The method of claim 1, wherein the moving includes:defining a path within the body using the insertion tool; and moving thedistal end portion of the insertion tool such that the stimulationportion of the electronic implant is disposed within the path and theterminal portion of the electronic implant is disposed within the path.3. The method of claim 1, wherein the moving includes moving the distalend portion of the insertion tool such that the stimulation portion ofthe electronic implant is disposed apart from the target location by apredetermined distance.
 4. The method of claim 1, wherein the movingincludes moving the distal end portion of the insertion tool such thatthe stimulation portion of the electronic implant is in contact with thetarget location.
 5. The method of claim 1, wherein the moving includesmoving the distal end portion of the insertion tool such that theterminal portion is a predetermined depth below an outer surface of theskin of the body.
 6. The method of claim 1, wherein the insertingincludes inserting the insertion tool such that a longitudinal axis ofthe insertion tool is offset from an outer surface of the skin of thebody by an angle less than 30 degrees.
 7. The method of claim 1, whereinthe target location is one of a median nerve, a peripheral nerve and asuperficially located nerve.
 8. The method of claim 1, wherein: theinsertion tool includes an insertion member and a guide member; theinserting includes inserting the insertion member of the insertion toolwithin the body; and the moving the distal end portion of the insertiontool within the body includes moving the guide member along an outersurface of the skin of the body such that the insertion member is movedwithin the body along a predetermined path.
 9. A method, comprising:operatively coupling an electrical device disposed outside of a body toa first electrode and a second electrode, the first electrode coupled toa first portion of a skin of the body, the second electrode coupled tothe second portion of the skin of the body; conveying an electricalsignal from the electrical device into the body via the first electrodesuch that a first portion of the electrical signal travels within thebody along a first path and a second portion of the electrical signaltravels within the body along a second path, the first path includingthe first portion of the skin, the second portion of the skin and atarget location within the body, the second path including the firstportion of the skin, the second portion of the skin and an electronicimplant disposed within the body.
 10. The method of claim 9, wherein theconveying includes conveying the electrical signal transcutaneously. 11.The method of claim 9, wherein the target location is one of a mediannerve, a peripheral nerve and a superficially located nerve.
 12. Themethod of claim 9, wherein the second path includes a terminal portionof the electronic implant.
 13. The method of claim 9, wherein at leastone of the first electrode or the second electrode are disposed on anouter surface of the skin directly above a terminal portion of theelectronic implant.
 14. The method of claim 9, wherein at least one ofthe first electrode or the second electrode are disposed on an outersurface of the skin directly above the target location.
 15. The methodof claim 9, wherein the second path includes a terminal portion of theelectronic implant, the electronic implant includes a stimulationportion disposed adjacent the target location.
 16. The method of claim9, wherein the first path is a first stimulation path and the secondpath is a second stimulation path.
 17. An apparatus, comprising: animplant delivery tool configured to deliver at least a portion of anelectronic implant within a body, the implant delivery tool having aguide member configured to be moved along an outer surface of the bodybetween a first position and a second position, the second positionbeing laterally spaced from the first position, an insertion membercoupled to the guide member such that (1) an angle is formed between aproximal end portion of the insertion member and a proximal end portionof the guide member, and (2) the portion of the electronic implant canbe delivered at a predetermined insertion angle of up to 30 degrees withrespect to the outer surface of the body, and a handle coupled to theguide member and the insertion member, the handle configured toselectively adjust the angle formed between the proximal end portion ofthe insertion member and the proximal end portion of the guide member.